Inverse Hartmann test for radius of curvature measurement in a corneal topography calibration sphere.

In this article, the use of a square Hartmann screen test to measure the radius of curvature of a corneal topography calibration test sphere is presented. The proposed technique is based on the image formation principle by specular reflection on convex reflective surfaces. Applying an inverse Hartmann test, a de-magnified virtual image (Hartmanngram) is obtained; considering their own scaled reference screen plate, a zonal wavefront retrieval approach is used and the radius of curvature obtained. Experimental setup along the obtained results is presented. A simulated spherical wavefront is used as a method to evaluate the error in the wavefront reconstruction. Since the measurements of radius of curvature fits in to ISO 10343, through suitable modifications the proposed method is potentially applicable in small F/# convex specular surfaces, as is the case in keratometry and corneal topography measurements.

Joint assessment of density correlations and fluctuations for analysing spatial tree patterns.

Inferring the processes underlying the emergence of observed patterns is a key challenge in theoretical ecology. Much effort has been made in the past decades to collect extensive and detailed information about the spatial distribution of tropical rainforests, as demonstrated, e.g. in the 50 ha tropical forest plot on Barro Colorado Island, Panama. These kinds of plots have been crucial to shed light on diverse qualitative features, emerging both at the single-species or the community level, like the spatial aggregation or clustering at short scales. Here, we build on the progress made in the study of the density correlation functions applied to biological systems, focusing on the importance of accurately defining the borders of the set of trees, and removing the induced biases. We also pinpoint the importance of combining the study of correlations with the scale dependence of fluctuations in density, which are linked to the well-known empirical Taylor's power law. Density correlations and fluctuations, in conjunction, provide a unique opportunity to interpret the behaviours and, possibly, to allow comparisons between data and models. We also study such quantities in models of spatial patterns and, in particular, we find that a spatially explicit neutral model generates patterns with many qualitative features in common with the empirical ones.

Microcephaly epidemic in Brazil: An earlier chapter.

OBJECTIVE: Identify risk factors for microcephaly and evaluate historical trends of microcephaly and arboviruses to recognize patterns and anomalies that indicate the beginning of the microcephaly epidemic associated with Zika infection. METHODS: The head circumferences of 62,298 newborns was analyzed to identify cases of microcephaly between 2014 and 2017. We compared the groups of newborns with normal head circumferences and those with microcephaly to identify risk factors. A time series with the incidences of microcephaly was analyzed to assess the appearance of anomalous values in order to identify the beginning of the microcephaly epidemic. Data on the incidence of dengue fever was used to develop a control chart, aiming to identify changes in incidence and seasonality that could suggest the circulation of a new arbovirus. FINDINGS: Premature newborns, children of mothers under 20 years of age and those born in 2014 and 2015 had a higher risk of microcephaly. Three quarters with anomalous incidences of microcephaly were identified, the first in 2014 and the others in 2015. The dengue fever epidemic curve in 2013 shows persistence of high incidences in atypical periods, suggesting the entry of a new virus in the 3rd and 4th quarters. CONCLUSIONS: These findings represent epidemiological evidence of the existence of cases of Zika virus between the 2nd quarter of 2013 and the beginning of 2014. The results add new elements to understanding the Zika virus epidemic in the Americas.

[Image-guided brachyablation for hepatocarcinoma. Report of one case]. / Image-Guided BrachyAblation (IGBA) en hepatocarcinoma. Descripción de la técnica y reporte del primer caso en Chile.

Eighty percent of hepatocarcinomas are inoperable at the moment of diagnosis. Liver transplantation is the treatment of choice in these cases, but local therapies are another alternative. Among these, Image-Guided BrachyAblation is a safe choice. We report a 76-year-old male with a hepatocarcinoma, who was considered inoperable due to the high surgical risk of the patient. A local treatment with Image-Guided BrachyAblation was decided. A brachytherapy needle was placed in the tumor under computed tomography guidance and a 15 Gy single dose was delivered from an Iridium-192 source. The patient had no immediate complications and at one month of follow up he continued without incidents.

Image-Guided BrachyAblation (IGBA) en hepatocarcinoma: descripción de la técnica y reporte del primer caso en Chile / Image-guided brachyablation for hepatocarcinoma: report of one case

Eighty percent of hepatocarcinomas are inoperable at the moment of diagnosis. Liver transplantation is the treatment of choice in these cases, but local therapies are another alternative. Among these, Image-Guided BrachyAblation is a safe choice. We report a 76-year-old male with a hepatocarcinoma, who was considered inoperable due to the high surgical risk of the patient. A local treatment with Image-Guided BrachyAblation was decided. A brachytherapy needle was placed in the tumor under computed tomography guidance and a 15 Gy single dose was delivered from an Iridium-192 source. The patient had no immediate complications and at one month of follow up he continued without incidents.

Neuroadaptive changes and behavioral effects after a sensitization regime of MDPV.

3,4-methylenedioxypyrovalerone (MDPV) is a synthetic cathinone with cocaine-like properties. In a previous work, we exposed adolescent mice to MDPV, finding sensitization to cocaine effects, and a higher vulnerability to cocaine abuse in adulthood. Here we sought to determine if such MDPV schedule induces additional behavioral-neuronal changes that could explain such results. After MDPV treatment (1.5 mg kg-1, twice daily, 7 days), mice were behaviorally tested. Also, we investigated protein changes in various brain regions. MDPV induced aggressiveness and anxiety, but also contributed to a faster habituation to the open field. This feature co-occurred with an induction of ΔFosB in the orbitofrontal cortex that was higher than its expression in the ventral striatum. Early after treatment, D2R:D1R ratio pointed to a preponderance of D1R but, upon withdrawal, the ratio recovered. Increased expression of Arc, CDK5 and TH, and decrease in DAT protein levels persisted longer after withdrawal, pointing to a neuroplastic lasting effect similar to that involved in cocaine addiction. The implication of the hyperdopaminergic condition in the MDPV-induced aggressiveness cannot be ruled out. We also found an initial oxidative effect of MDPV, without glial activation. Moreover, although initially the dopaminergic signal induced by MDPV resulted in increased ΔFosB, we did not observe any change in NFκB or GluA2 expression. Finally, the changes observed after MDPV treatment could not be explained according to the autoregulatory loop between ΔFosB and the epigenetic repressor G9a described for cocaine. This provides new knowledge about the neuroadaptive changes involved in the vulnerability to psychostimulant addiction.

Diabetes mellitus mortality in Spanish cities: Trends and geographical inequalities.

AIM: To analyze the geographical pattern of diabetes mellitus (DM) mortality and its association with socioeconomic factors in 26 Spanish cities. METHODS: We conducted an ecological study of DM mortality trends with two cross-sectional cuts (1996-2001; 2002-2007) using census tract (CT) as the unit of analysis. Smoothed standardized mortality rates (sSMR) were calculated using Bayesian models, and a socioeconomic deprivation score was calculated for each CT. RESULTS: In total, 27,757 deaths by DM were recorded, with higher mortality rates observed in men and in the period 1996-2001. For men, a significant association between CT deprivation score and DM mortality was observed in 6 cities in the first study period and in 7 cities in the second period. The highest relative risk was observed in Pamplona (RR, 5.13; 95% credible interval (95%CI), 1.32-15.16). For women, a significant association between CT deprivation score and DM mortality was observed in 13 cities in the first period and 8 in the second. The strongest association was observed in San Sebastián (RR, 3.44; 95%CI, 1.25-7.36). DM mortality remained stable in the majority of cities, although a marked decrease was observed in some cities, including Madrid (RR, 0.67 and 0.64 for men and women, respectively). CONCLUSIONS: Our findings demonstrate clear inequalities in DM mortality in Spain. These inequalities remained constant over time are were more marked in women. Detection of high-risk areas is crucial for the implementation of specific interventions.

The combination of MDPV and ethanol results in decreased cathinone and increased alcohol levels. Study of such pharmacological interaction.

Methylenedioxypyrovalerone (MDPV) is a new psychostimulant cathinone acting as a selective dopamine transporter blocker. Due to the concomitant consumption of ethanol (EtOH) and new psychoactive substances, it is of interest to explore a possible pharmacological interaction between MDPV and EtOH. In locomotor activity assays, EtOH (1g/kg i.p.) elicited a reduction in the stimulant effect induced by low doses of MDPV (0.1-0.3mg/kg, s.c.) in rats, jointly with a decrease in blood and brain MDPV concentrations. Experiments in rat liver microsomes showed different effects depending on the [MDPV]/[EtOH] relationship, evidencing, at certain concentrations, the enhancing effect of EtOH on MDPV metabolism. These suggest that EtOH interacts with MDPV at microsomal level, increasing its metabolic rate. The interaction between both substances was also supported by results in plasma EtOH concentration, which were significantly increased by MDPV, in such a manner that EtOH elimination rate was significantly reduced. The possible toxicological impact of this phenomenon deserves further investigation. In contrast, the rewarding properties of MDPV were unaltered by EtOH. Microdialysis experiments verified that, in the NAcc, both substances could also act synergistically, in such a manner that extracellular dopamine concentrations are maintained. Finally, if the psychostimulant effect induced by MDPV decreased with EtOH, it could favor the boosting and re-dosing in search of the desired effects. However, as the rewarding effect of each dose of the substance would not decrease, the addictive liability could increase considerably. Moreover, we must warn about the increase in EtOH concentrations when consumed concomitantly with MDPV.

Measurement of spherical and cylindrical power in ophthalmic lenses based in the change of lateral amplification.

In this article, we present a new technique to measure spherical and cylindrical power in ophthalmic lenses. This method is based in the change of lateral amplification produced by an optical system when introducing an ophthalmic lens. Ophthalmic lens power is calculated by considering the change in image size from a reference object and its own image seen through the ophthalmic lens. Mathematical analysis is presented along with the experimental setup and the obtained results. Several algorithms were applied to the obtained results as a method to compensate the error in order to fit into ISO 8598 specifications.

Relationship between human paraoxonase-1 activity and PON1 polymorphisms in Mexican workers exposed to organophosphate pesticides.

Paraoxonase-1 (PON1) is a serum enzyme which catalyzes the hydrolysis of organophosphate pesticides. In this study we conducted a cross-sectional study and reported on the distribution of three common genetic polymorphisms of the PON1 gene in a population of floriculture workers from Mexico as well as the association between those polymorphisms and other predictors with serum PON1 activity on paraoxon, diazoxon and phenylacetate. The genotype frequencies at position PON1(55) were 89% (LL), 10% (LM) and 0.6% (MM), at position PON1(192) they were 16% (QQ), 47% (QR) and 37% (RR), and 26% (TT), 42% (TC) and 32% (CC) at position PON1(-108). Thus, the frequencies of alleles L, Q and T were 0.94, 0.40 and 0.47, respectively. The PON1(55) polymorphism had no significant effect on serum PON1 activity on any substrate. We found a significant association between the PON1(192) polymorphism and PON1 activity towards paraoxon and diazoxon, which increased in genotypes as follows: 192RR>192QR>192QQ for paraoxonase activity and, inversely, 192QQ>192QR>192RR for diazoxonase activity. The PON1(-108) polymorphism also had a significant effect on PON1 activity level towards paraoxon in the following order among the genotype groups: -108CC>-108TC>-108TT. Serum PON1 activity towards diazoxon was not associated with the PON1(-108) polymorphism but it was influenced by the intensity exposure to pesticides at the floriculture industry and the years of the occupational exposure to pesticides. No polymorphism significantly influenced serum PON1 activity on phenylacetate.

Biological and phylogenetic characterization of virulent Newcastle disease virus circulating in Mexico.

In 2002-2003, velogenic Newcastle Disease Virus outbreaks, closely related to the Mexican isolates, were confirmed in the United States (U.S.) in southern California, Arizona, Nevada, and Texas. In this report, virulent NDVs isolated in Mexico between 1998 and 2006 were subjected to biologic characterization, using standard pathogenicity tests, and to phylogenetic analysis. Chicken embryo mean death time (MDT) test results ranged from 39.7 to 61.5 hours, and intracerebral pathogenicity index (ICPI) values were between 1.59 and 1.94, compared to a possible maximum value of 2.0. These isolates showed a dibasic amino acid motif at the fusion protein cleavage site sequence required for host systemic replication. Phylogenetic analysis indicated that the Mexican virulent NDVs belong to the class II, genotype V viruses and can be clearly divided in two groups as follows: isolates from 1998 to 2001 with close epidemiologic relationship with the latest U.S. NDV outbreaks, and phylogenetically distinct viruses, isolated from 2004 to 2006, which showed higher virulence. The assessment of the evolution of viruses from Mexico and other neighboring countries will aid in the U.S surveillance efforts for early detection of highly virulent NDV.

Enclavijado lateral en fracturas supracondíleas de húmero / Pegged lateral supracondylar fractures of the humerus

Las fracturas supracondíleas se producen con mayor frecuencia entre los 5 a 8 años de edad. La facilidad actual de contar con un intensificador de imagen ha revolucionado el tratamiento de estas fracturas, las cuales se pueden reducir de manera cerrada y a la vez fijarlas percutáneamente. Se revisaron las Historias Clínicas de pacientes que acudieron al Hospital Baca Ortiz durante el 2005 con fracturas supracondíleas Gil inestable y GIII de Gartland. En 75 niños se utilizó la técnica de enclavijado cruzado y 25 niños fueron intervenidos con la técnica de enclavijado lateral. Se presentó un 9% de lesión iatrogénica del nervio cubital en el grupo intervenido con técnica de clavijas cruzadas, que consistieron en neuropraxias y axonotmesis. En el grupo de clavijas laterales no se reportó lesiones neurológicas añadidas. Las clavijas laterales proporcionan una buena estabilización de las fracturas.

Avian adeno-associated virus-based expression of Newcastle disease virus hemagglutinin-neuraminidase protein for poultry vaccination.

The avian adeno-associated virus (AAAV) is a replication-defective nonpathogenic virus member of the family Parvoviridae that has been proved to be useful as a viral vector for gene delivery. The use of AAAV for transgenic expression of Newcastle disease virus (NDV) hemagglutinin-neuraminidase (HN) protein and its ability to induce immunity in chickens were assessed. Proposed advantages of this system include no interference with maternal antibodies, diminished immune response against the vector, and the ability to accommodate large fragments of genetic information. In this work the generation of recombinant AAAV virions expressing the HN protein (rAAAV-HN) was demonstrated by electron microscopy, immunocytochemistry, and western blot analysis. Serological evidence of HN protein expression after in ovo or intramuscular inoculation of the recombinant virus in specific-pathogen-free chickens was obtained. Serum from rAAAV-HN-vaccinated birds showed a systemic immune response evidenced by NDV-specific enzyme-linked immunosorbent assay and hemagglutination inhibition testing. Positive virus neutralization in embryonated chicken eggs and indirect immunofluorescence detection of NDV infected cells by serum from rAAAV-HN vaccinated birds is also reported. A vaccine-challenge experiment in commercial broiler chickens using a Venezuelan virulent viscerotropic strain of NDV was performed. All unvaccinated controls died within 5 days postchallenge. Protection up to 80% was observed in birds vaccinated in ovo and revaccinated at 7 days of age with the rAAAV-HN. The results demonstrate the feasibility of developing and using an AAAV-based gene delivery system for poultry vaccination.

Protection against infectious bursal disease virulent challenge conferred by a recombinant avian adeno-associated virus vaccine.

The development and use of recombinant vaccine vectors for the expression of poultry pathogens proteins is an active research field. The adeno-associated virus (AAV) is a replication-defective virus member of the family Parvoviridae that has been successfully used for gene delivery in humans and other species. In this experiment, an avian adeno-associated virus (AAAV) expressing the infectious bursal disease virus (IBDV) VP2 protein (rAAAV-VP2) was evaluated for protection against IBDV-virulent challenge. Specific pathogen free (SPF) birds were inoculated with rAAAV-VP2 or with a commercial intermediate IBDV vaccine and then challenged with the Edgar strain. IBDV-specific antibody levels were observed in all vaccinated groups; titers were higher for the commercial vaccine group. The live, commercial vaccine induced adequate protection against morbidity and mortality; nevertheless, initial lymphoid depletion and follicular atrophy related to active viral replication was observed as early as day 14 and persisted up to day 28, when birds were challenged. No bursal tissue damage due to rAAAV-VP2 vaccination was observed. Eight-out-of-ten rAAAV-VP2-vaccinated birds survived the challenge and showed no clinical signs. The bursa:body weight ratio and bursa lesion scores in the rAAAV-VP2 group indicated protection against challenge. Therefore, transgenic expression of the VP2 protein after rAAAV-VP2 vaccination induced protective immunity against IBDV challenge in 80% of the birds, without compromising the bursa of Fabricius. The use of rAAAV virions for gene delivery represents a novel approach to poultry vaccination.

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Genetic characterization, pathogenicity, and protection studies with an avian adenovirus isolate associated with inclusion body hepatitis.

An avian adenovirus (AAV) was isolated from liver samples of two 2-wk-old broiler-breeder flocks obtained from grandparents vaccinated at 10 and 17 wks of age with an autogenous inactivated vaccine containing the European AAV 8 (8565 strain) and 11 (1047 strain) serotypes (AAV8/11 vaccine). Affected broiler-breeders exhibited clinical signs and macroscopic and microscopic lesions associated with inclusion body hepatitis (IBH). The isolated adenovirus, identified as Stanford, was molecularly characterized as European serotype 9. The pathogenicity of the Stanford strain was confirmed after inoculation of specific-pathogen-free (SPF) chickens at 1-7 days of age, causing 100% and 20% mortality, respectively. The level of protection against IBH was evaluated in two broiler-breeder progenies from AAV 8/11-vaccinated grandparent flocks and a commercial broiler flock by challenge at 1 or 7 days of age with the AAV 8 and 11 serotypes and/or the Stanford strain. The broiler-breeder progenies and the commercial broiler flock exhibited protection against IBH after challenge. No significant differences in mean body weights were observed at 3 wk of age in any of the evaluated groups. We conclude that broiler-breeder progenies from 30- to 50-wk-old grandparents vaccinated with the AAV 8/11 vaccine were adequately protected against challenge with the AAV 8 and 11 serotypes and the Stanford strain.

Detection of Massachusetts and Arkansas serotypes of infectious bronchitis virus in broilers.

The objective of this study was to compare the presence of the Arkansas (Ark) and Massachusetts (Mass) serotypes of infectious bronchitis virus (IBV) in the tracheas and cecal tonsils of commercial broilers after vaccination at 1 day of age by coarse spray. When given as a single serotype vaccine, the Mass strain was detected by reverse transcriptase-polymerase chain reaction (RT-PCR)-restriction fragment length polymorphism (RFLP) only in the tracheas, whereas the Ark strain was detected in both the tracheas and cecal tonsils. By in situ hybridization, the Mass and Ark nucleocapsid (Nc) genes were detected only at 7 days in the tracheas. When both strains were given in the mixed vaccine, the Mass strain was more consistently detected by RT-PCR-RFLP in the tracheas and cecal tonsils at early stages of infection (up to 14 days) and the Arkansas strain was more consistently detected at late stages of infection (21 and 28 days). By in situ hybridization, the IBV Nc gene was more consistently detected in the trachea at early stages of infection (7, 14, and 21 days) and in the cecal tonsils at late stages of infection (21, 28, and 35 days). In general, the Mass strain was more frequently recovered from the tracheal and cecal tonsil tissues at earlier stages of infection and the Ark strain was recovered at later stages of infection.

Molecular characterization of avian infectious bronchitis virus strains isolated in Colombia during 2003.

Sixteen infectious bronchitis virus (IBV) isolates were recovered from broilers and layers from five geographic poultry regions in Colombia. The viruses were isolated from tracheas, lungs, and cecal tonsils of birds, previously vaccinated with the Massachusetts strain, that were showing respiratory signs. Further analysis of the IBV isolates was achieved by phylogenetic analysis comparing their deduced amino acid sequences in the hypervariable region 1 of the S1 gene with reference strains. Four unique genotype clusters containing isolates with indigenous genotypes were observed. One isolate was found to be the Connecticut genotype and three isolates were found to be the Massachusetts genotype.

Sequence analysis, viral rescue from infectious clones and generation of recombinant virions of the avian adeno-associated virus.

Aiming at the generation of a viral-vectored system for gene delivery and vaccination in poultry, the entire genomes of the VR-865 and DA-1 strains of the avian adeno-associated virus have been cloned and sequenced. Sequence analysis of the clones showed that the genomic distribution of the structural and non-structural protein-coding genes of these viruses is conserved and in agreement with what has been previously described for the primate adeno-associated viruses. Amino acid differences between the avian adeno-associated viruses and the primate adeno-associated viruses are more evident in the genes that code for the non-structural (Rep) proteins of the virus, while the Cap region amino acid sequence was found to be more conserved. Since all the regulatory and coding sequences of the virus were present in the plasmids obtained, complete infectious viral particles were rescued from these clones, and these rescued viral populations were amplified by co-infecting primary embryo liver cells with the rescued virus and the CELO strain of the avian adenovirus type 1. As a proof of concept of the validity of this system for the purpose of gene delivery, recombinant viruses encoding for the LacZ gene as a reporter system were also generated. These recombinant viruses were used to express beta galactosidase activity in primary chicken embryo cell cultures.